The many faces of early repolarization syndrome: A single-center case series.

BACKGROUND:Early repolarization syndrome (ERS) is a rare but increasingly recognized cause of malignant ventricular arrhythmias. OBJECTIVE:The purpose of this study was to characterize the presentations and treatments of ERS at our institution. METHODS:We performed a retrospective chart review of all patients presenting to our institution between 2008 and 2019 with ERS. Exclusion criteria included Brugada syndrome, positive provocative testing with class I antiarrhythmic drugs, metabolic disturbances, or structural heart disease. RESULTS:Of 10 patients identified with ERS, 8 were men with a mean age of 30 ± 17 years at diagnosis. Documented arrhythmias included ventricular fibrillation in 7 of 10, polymorphic ventricular tachycardia in 3 of 10, and monomorphic ventricular tachycardia in 3 of 10 patients. Atrial fibrillation was diagnosed in 3 of 10, and atrioventricular block was seen in 2 of 10. J waves and/or electrocardiographic early repolarization patterns were dynamic in 7 of 10. Arrhythmias occurred at rest in 8 of 10 and with exertion in 2 of 10. Only 1 patient had a family history of sudden death, and 4 of 10 patients had variants of uncertain significance on genetic testing. Quinidine effectively suppressed arrhythmias in 5 of 5 patients but required dose escalation to >1 g/d in 3 of 5 patients. Abnormal epicardial electrograms were recorded over the inferolateral left ventricle in 2 patients who underwent mapping and were successfully ablated. Premature ventricular contraction triggers were also targeted for ablation in 3 patients. CONCLUSION:ERS is a heterogeneous condition and may be associated with both atrial and ventricular arrhythmias, atrioventricular block, dynamic electrocardiographic changes, and variable triggers. In addition to targeting premature ventricular contraction triggers, mapping and ablation of abnormal epicardial electrograms may be a potential future treatment strategy.